ci: check public headers conform to c++ ISO standards #4138

Job	Run time
Build mlibc (x86_64, mlibc, gcc)	3m 39s
Compile sysdeps (dripos)	2m 16s
Compile sysdeps (lemon)	54m 13s
Compile sysdeps (aero)	8m 57s
Build mlibc (x86_64, mlibc-static, gcc)	3m 8s
Compile sysdeps (ironclad)	2m 18s
Build mlibc (x86_64, mlibc-shared, gcc)	3m 1s
Compile sysdeps (lyre)	54m 11s
Build mlibc (x86_64, mlibc-ansi-only, gcc)	5m 16s
Compile sysdeps (keyronex)	2m 21s
Build mlibc (x86_64, mlibc-headers-only, gcc)	2m 3s
Compile sysdeps (managarm)	9m 10s
Build mlibc (riscv64, mlibc, gcc)	3m 46s
Compile sysdeps (vinix)	2m 16s
Build mlibc (riscv64, mlibc-static, gcc)	4m 28s
Compile sysdeps (astral)	2m 16s
Build mlibc (riscv64, mlibc-shared, gcc)	3m 4s
Build mlibc (riscv64, mlibc-ansi-only, gcc)	2m 54s
Build mlibc (riscv64, mlibc-headers-only, gcc)	2m 34s
Build mlibc (aarch64, mlibc, gcc)	4m 4s
Build mlibc (aarch64, mlibc-static, gcc)	55m 13s
Build mlibc (aarch64, mlibc-shared, gcc)	55m 8s
Build mlibc (aarch64, mlibc-ansi-only, gcc)	55m 3s
Build mlibc (aarch64, mlibc-headers-only, gcc)	1m 59s
Build mlibc (x86, mlibc, gcc)	3m 54s
Build mlibc (x86, mlibc-static, gcc)	3m 10s
Build mlibc (x86, mlibc-shared, gcc)	5m 41s
Build mlibc (x86, mlibc-ansi-only, gcc)	2m 59s
Build mlibc (x86, mlibc-headers-only, gcc)	1m 58s
Build mlibc (m68k, mlibc, gcc)	10m 3s
Build mlibc (m68k, mlibc-static, gcc)	4m 49s
Build mlibc (m68k, mlibc-shared, gcc)	2m 58s
Build mlibc (m68k, mlibc-ansi-only, gcc)	8m 19s
Build mlibc (m68k, mlibc-headers-only, gcc)	8m 41s
Build mlibc (x86_64, mlibc, clang)	3m 17s
	6h 39m 7s

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